1. Field
The described technology generally relates to a secondary battery, and more particularly, to a secondary battery having improved lifetime and productivity.
2. Description of the Related Technology
Recent secondary batteries, used as power sources of a cellular phone, a notebook computer, a camcorder, etc., are small in size and large in capacity. Such a secondary battery is generally manufactured by accommodating an electrode assembly in a battery case, injecting an electrolyte into the battery case and then sealing the battery case. Here, the electrode assembly is formed by respectively coating active materials on positive and negative electrode collectors and then interposing a separator between the positive and negative electrode collectors.
The secondary battery may be divided into a cylinder-type battery using a cylindrical can, a prism-type battery using a prismatic can and a pouch-type battery using a thin-film pouch case made of a thin plate, according to the external appearance of a case having an electrode assembly accommodated therein. The electrode assembly is divided into i) a winding-type electrode assembly formed by winding a positive electrode collector, a separator and a negative electrode collector, which are sequentially stacked, and ii) a stacking-type electrode assembly formed by stacking a plurality of positive electrode collectors, a plurality of separators and a plurality of negative electrode collectors.